1239

Holy Roman Emperor Frederick II has defeated the Lombard League and seems on the verge of conquering the Papal States, leading Pope Gregory IX to excommunicate him and denounce him as a heretic. Frederick responds by expelling Catholic priests from Lombardy and capturing and sinking several vessels carrying Catholic prelates to synod in Rome, although he does not actually conquer the Papal States as feared.

Pope Gregory IX, under the influence of Jewish convert to Christianity Nicholas Donin, orders the burning of all copies of the Jewish Talmud in Christendom. After several years of rounding up the copies, more than 12,000 copies of the Talmud will be burned in Paris in 1242.